Room temperature gas sensor based on porous silicon/metal oxide structure

N-type TiO2-x and In2O3 center dot SnO2 thin films were deposited onto p-type porous silicon layer which was formed by common electrochemical anodization. The current-voltage characteristics of obtained structures and sensitivity to different concentrations of hydrogen in air were studied. Measurements were carried out at room temperature. As shown results of measurements, an exponential growth of the current in forward branch of the current-voltage characteristics of the device made of TiO2-x layer was detected. Higher sensitivity to hydrogen of the TiO2-x-porous silicon sensor in comparison to structure made of In2O3 center dot SnO2 film was detected at room temperature (without preheating of work body of the sensor). (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.